JP5184577B2 - Disc recording medium, disc drive apparatus, and playback method - Google Patents

Description

  The present invention relates to a disk recording medium such as an optical disk, a disk manufacturing method for manufacturing the disk recording medium, a disk drive device for the disk recording medium, and a playback method, and in particular, a disk with tracks wobbled as a pregroove. It is about.

As a technique for recording / reproducing digital data, optical disks (including magneto-optical disks) such as CD (Compact Disk), MD (Mini-Disk), and DVD (Digital Versatile Disk) are used as recording media. There is data recording technology. An optical disk is a generic term for recording media that irradiate laser light onto a disk in which a thin metal plate is protected with plastic, and read signals by changes in reflected light.
The optical disc includes, for example, a read-only type as known as CD, CD-ROM, DVD-ROM, MD, CD-R, CD-RW, DVD-R, DVD-RW, DVD + RW, DVD -There is a type in which user data can be recorded as known in RAM and the like. In the recordable type, data can be recorded by using a magneto-optical recording method, a phase change recording method, a dye film change recording method, or the like. The dye film change recording method is also called a write-once recording method, and can be recorded only once and cannot be rewritten. On the other hand, the magneto-optical recording method and the phase change recording method can rewrite data and are used for various purposes such as recording of various content data such as music, video, games, application programs and the like.

In order to record data on a recordable disc such as a magneto-optical recording method, a dye film change recording method, a phase change recording method, etc., a guide means for tracking the data track is required. Grooves (grooves) are formed in advance as pregrooves, and the grooves or lands (cross-section plateau-like portions sandwiched between the grooves and the grooves) are used as data tracks.
Further, it is necessary to record address information so that data can be recorded at a predetermined position on the data track, but this address information may be recorded by wobbling (meandering) the groove.

That is, a track for recording data is formed in advance as a pregroup, for example, and the side wall of this pregroup is wobbled corresponding to the address information.
In this way, the address can be read from the wobbling information obtained as reflected light information at the time of recording or reproduction. For example, even if pit data indicating the address is not formed on the track in advance, the desired position can be read. Data can be recorded and reproduced.
By adding address information as a wobbling groove in this way, for example, it becomes unnecessary to provide an address area discretely on a track and record an address as, for example, pit data. Recording capacity can be increased.
The absolute time (address) information expressed by such a wobbling groove is called ATIP (Absolute Time In Pregroove) or ADIP (Adress In Pregroove).

In recent years, in addition to address information and information recorded and reproduced by users, it has become necessary to record various types of information on a disk in advance, as with address information.
That is, as pre-recorded information recorded on the disc in advance, disc information indicating recording conditions on the disc, such as disc linear information indicating the recording linear velocity and recommended laser power, and copy protection information for excluding hacked devices are recorded. Want to. In particular, copy protection information is important.

As a method for prerecording various information on a disc, it is known to form embossed pits on the disc.
However, in consideration of high-density recording / reproducing on an optical disc, the pre-recording method using embossed pits is inconvenient.

In the case of recording / reproducing with high density on an optical disc, it is necessary to reduce the depth of the groove. In a disc in which grooves and embossed pits are produced simultaneously by a stamper, it is very difficult to make the depths of grooves and embossed pits different. For this reason, the depth of the embossed pits must be the same as the depth of the grooves.
However, when the depth of the emboss pit becomes shallow, there is a problem that a signal with good quality cannot be obtained from the emboss pit.

For example, a laser diode with a wavelength of 405 nm and an objective lens with NA = 0.85 are used as an optical system, and a track pitch is 0.32 μm and a linear density is 0.12 μm / bit on a disk with a cover (substrate) thickness of 0.1 mm. By recording and reproducing the phase change mark (phase change mark), it is possible to record and reproduce a capacity of 23 GB (gigabytes) on an optical disk having a diameter of 12 cm.
In this case, the phase change mark is recorded / reproduced on a groove formed in a spiral shape on the disc. However, in order to suppress media noise for higher density, the groove depth is about 20 nm, that is, Λ / 13 to λ / 12 is preferable for the wavelength λ.
On the other hand, in order to obtain a good quality embossed pit signal, the depth of the embossed pit is preferably λ / 8 to λ / 4. Was not obtained.
Under these circumstances, a method for pre-recording information instead of embossed pits has been demanded.

  In view of these circumstances, the present invention provides a novel optical recording medium using a prerecording method suitable for increasing the capacity and improving the recording / reproducing performance as a disk recording medium, and a disk manufacturing method for manufacturing the same, and Disk drive device. An object is to provide a reproduction method.

For this purpose, the disk recording medium of the present invention has a groove for forming a track on the disk formed in a spiral shape, and address information is recorded by wobbling the groove, and the track formed by the groove. Has a recording / playback area used for recording / playback of the recording mark, and a playback-only area in which pre-recorded information is recorded by wobbling the groove, and the data recorded with the recording mark in the recording / playback area is: a frame synchronization signal which is arranged at the head, the long distance code error correction encoded 38 and the user data that is separated by the byte-by-byte, burst error detection which is inserted for each user data divided for each said 38 bytes It consists of a predetermined number of units consisting of codes Unit of data recorded in a recording mark in the band, the three burst error detection code during four of the user data is composed is inserted, the predetermined number of data to be recorded by the recording marks on the recording and reproduction area The address information by wobbling of the groove in the section corresponding to the unit is composed of a plurality of address blocks composed of a sync part and a data part, and the sync part is a first sync block composed of a monotone bit and a first sync bit. A second sync block composed of a monotone bit and a second sync bit, a third sync block composed of a monotone bit and a third sync bit, and a fourth sync block composed of a monotone bit and a fourth sync bit Is done.

In the disk drive device of the present invention, a groove for forming a track on the disk is formed in a spiral shape, address information is recorded by wobbling the groove, and a track formed by the groove is a recording mark. A recording / playback area used for recording / playback and a read-only area in which pre-recorded information is recorded by wobbling the groove, and data recorded with a recording mark in the recording / playback area is arranged at the head. from the frame synchronization signal and the user data being partitioned into 38 bytes error correction coding with long distance code, a burst error detection code is inserted for each user data divided for each said 38 bytes It consists of a predetermined number of units Unit of data recorded in recording marks, four three burst error detection code during said user data is constructed by inserting said predetermined number of units of data recorded by the recording marks on the recording and reproduction area The address information by wobbling of the groove in the section corresponding to is composed of a plurality of address blocks consisting of a sync part and a data part, and the sync part is a first sync block consisting of a monotone bit and a first sync bit, a monotone A second sync block consisting of a bit and a second sync bit, a third sync block consisting of a monotone bit and a third sync bit, and a fourth sync block consisting of a monotone bit and a fourth sync bit A data recording / reproducing data to / from a disk recording medium. A disk drive device comprising: head means for irradiating the track with laser to obtain a reflected light signal; wobbling extracting means for extracting a signal related to wobbling of the track from the reflected light signal; and recording from the reflected light signal. Recording mark extraction means for extracting a signal related to mark information, and address decoding for performing MSK demodulation on the signal related to wobbling extracted by the wobbling extraction means and decoding the address information during reproduction of the recording / reproducing area And a phase change mark decoding means for performing decoding processing on the signal related to the recording mark extracted by the recording mark extracting means to obtain information recorded as a recording mark at the time of reproduction of the recording / reproducing area, and During playback of the playback-only area, the wob Pre-recorded information decoding means for decoding the signal related to the wobbling extracted by the ring extracting means to obtain the pre-recorded information.

In the reproducing method of the present invention, a groove for forming a track on a disk is formed in a spiral shape, address information is recorded by wobbling of the groove, and a track formed by the groove has a recording mark. It has a recording / playback area used for recording / playback and a playback-only area in which pre-recorded information is recorded by wobbling the groove, and data recorded with a recording mark in the recording / playback area is arranged at the head. a frame synchronization signal comprised of a user data is partitioned into 38 bytes error correction coding with long distance code, a burst error detection code is inserted for each user data divided for each said 38 bytes Consists of a predetermined number of units, with recording marks in the recording / playback area Unit of data recorded is composed of four are inserted three burst error detection code during said user data, corresponding to the predetermined number of units of data recorded by the recording marks on the recording and reproduction area Address information by wobbling of the groove in the section is composed of a plurality of address blocks including a sync part and a data part, and the sync part includes a first sync block including a monotone bit and a first sync bit , a monotone bit and a first sync bit. Disc recording medium comprising a second sync block comprising two sync bits, a third sync block comprising monotone bits and a third sync bit, and a fourth sync block comprising monotone bits and a fourth sync bit When playing back the recording / playback area Then, a signal related to the wobbling of the track and a signal related to the recording mark are extracted from the reflected light signal when the track is irradiated with laser, and the extracted address related to the wobbling is subjected to MSK demodulation and the address In addition to decoding the information, the signal related to the extracted recording mark is decoded to obtain information recorded as the recording mark. When reproducing the reproduction-only area, the track is irradiated with laser. A signal related to wobbling of the track is extracted from the reflected light signal, and the extracted signal related to wobbling is decoded to obtain the prerecorded information.

The main points of the present invention are as follows.
A recording / reproduction area and a reproduction-only area are formed by wobbling a groove formed in a spiral shape on the disk in order to form a track for tracking.
The recording / reproducing area is an area in which address information is recorded by groove wobbling, and information is recorded / reproduced by a phase change mark on a track formed by the groove in which the address information is recorded.
The reproduction-only area is an area in which prerecorded information is recorded by groove wobbling. This reproduction-only area is an area in which information by the phase change mark is not recorded.

In addition, the linear density for recording the pre-recorded information in the read-only area is smaller than the information linear density by the phase change mark in the recording / reproducing area and larger than the address information linear density.
The prerecorded information is copy protection information.
Pre-recorded information is modulated and recorded with an FM code.
The ECC (error correction code) format of pre-recorded information has the same code and structure as the ECC format of information recorded by phase change.
An error correction code including address information is added to the prerecorded information.
The synchronization signal of the pre-recorded information has a plurality of synchronization signals, each synchronization signal is composed of a pattern not included in the information modulation rule, an identification pattern for identifying each synchronization signal, and the identification pattern is Assume that the identification number and the even parity bit of the identification number are modulated by the FM code.

As will be understood from the above description, the present invention provides the following effects.
That is, the disk recording medium of the present invention forms a recording / reproducing area and a reproduction-only area by wobbling a spiral groove formed on the disk to form a track for tracking. The recording / playback area is an area where address information is recorded by groove wobbling, information is recorded / reproduced by a phase change mark on a track formed by the groove in which the address information is recorded, and a reproduction-only area is a groove wobbling area. Thus, the prerecorded information is recorded in the area.
This eliminates the need to record prerecorded information by embossed pits. And since it is not necessary to form an emboss pit, the depth of a groove can be made shallow. That is, the groove depth can be set to an optimum state for high-density recording without considering the reproduction characteristics of the emboss pits. Therefore, for example, high density recording that realizes a capacity of 23 GB or the like on a disk having a diameter of 12 cm is possible.
On the disk drive side, the prerecorded information can be reproduced (extracted from the wobble information) in the reproduction system of the same wobble channel as the address information (ADIP).

  Further, by recording copy protection information as pre-recorded information by a wobbling groove without forming embossed pits, a storage system suitable for a recording / playback system for video signals, audio signals, etc. can be constructed.

  In addition, the reproduction-only area is an area where information by the phase change mark is not recorded. Since the phase change mark can be said to be a mark for converting a recording layer having a high reflectivity to a low reflectivity, the track on which the phase change mark is recorded has an average lower reflectivity. That is, although the return light is reduced, this is disadvantageous in terms of SNR (Signal Noise Ratio) for extracting the wobbling component of the groove. In the present invention, the fact that the phase change mark is not recorded in the read-only area can prevent the SNR of the pre-recorded information from deteriorating and can obtain a high-quality wobbling signal.

The linear density for recording the pre-recorded information in the read-only area is smaller than the information linear density by the phase change mark in the recording / reproducing area and larger than the address information linear density.
By making the recording linear density of the pre-recorded information smaller than the recording linear density of the phase change mark, it is possible to reproduce the wobbling signal obtained from the push-pull signal with a lower SNR than the phase change mark with high quality.
Also, by making the recording linear density of prerecorded information larger than the linear density of address information (ADIP), the transfer rate can be increased and the reproduction time can be shortened.

  The prerecorded information is recorded after being modulated with an FM code. As a result, the signal band can be narrowed and the SNR can be improved. Further, both the PLL and the detection circuit can be configured with simple hardware.

  The ECC (error correction code) format of pre-recorded information has the same code and structure as the ECC format of information recorded by phase change. For this reason, the pre-recorded information and the phase change information can use the same hardware for the ECC processing, and the cost reduction and the simplification of the configuration of the disk drive device can be promoted.

  An error correction code including address information is added to the prerecorded information. As a result, the disk drive device can appropriately perform the access / reproduction operation based on the address in the reproduction-only area.

The synchronization signal of the pre-recorded information has a plurality of synchronization signals, each synchronization signal is composed of a pattern not included in the information modulation rule, an identification pattern for identifying each synchronization signal, and the identification pattern is The identification number and the even parity bit of the identification number are modulated by the FM code.
As a result, the position of each synchronization signal can be easily determined even in the middle of the ECC block, and the address in the ECC block can be easily detected. In addition, when identifying each synchronization signal pattern from a plurality of synchronization signal patterns, it is possible to check the correctness of the identification pattern by performing a parity check as well as identifying by the difference in the identification pattern. The signal can be identified with high accuracy.

  From the above, the present invention is suitable as a large capacity disk recording medium, the recording / reproducing operation performance of the disk drive device is improved, and the wobble processing circuit system can be simplified. .

It is explanatory drawing of the groove of the disk of embodiment of this invention. It is explanatory drawing of the area structure of the disk of embodiment. It is explanatory drawing of the wobbling system of the groove of the disk of embodiment. It is explanatory drawing of the modulation system of the prerecorded information of embodiment. It is explanatory drawing of the ECC structure of the phase change mark of embodiment. It is explanatory drawing of the ECC structure of the prerecorded information of embodiment. It is explanatory drawing of the frame structure of the phase change mark and pre-recorded information of embodiment. It is explanatory drawing of the frame sync of the pre-recorded information of embodiment. It is explanatory drawing of the frame sync arrangement | positioning of the prerecorded information of embodiment. It is explanatory drawing of the BIS structure of the prerecorded information of embodiment. It is explanatory drawing of the BIS structure of the prerecorded information of embodiment. It is explanatory drawing of the BIS structure of the prerecorded information of embodiment. It is explanatory drawing of the BIS structure of the prerecorded information of embodiment. It is explanatory drawing of the address unit of the prerecorded information of embodiment. It is explanatory drawing of the modulation system of ADIP information of embodiment. It is explanatory drawing of the address block with respect to RUB of embodiment. It is explanatory drawing of the sync part of the disk of embodiment. It is explanatory drawing of the sync bit pattern of the disk of embodiment. It is explanatory drawing of the data part of the disc of embodiment. It is explanatory drawing of the ADIP bit pattern of the disk of embodiment. It is explanatory drawing of the ECC structure of ADIP information of embodiment. 1 is a block diagram of a disk drive device according to an embodiment. It is a block diagram of the MSK demodulator of the disk drive device of the embodiment. It is explanatory drawing of the MSK demodulation process of the disk drive apparatus of embodiment. It is a block diagram of the cutting apparatus which manufactures the disk of embodiment.

Hereinafter, an optical disk as an embodiment of the present invention will be described, and a disk drive device (recording / reproducing apparatus) and a manufacturing method corresponding to the optical disk will be described in the following order.

1. Disc 1-1. Physical characteristics of optical disc 1-2. Pre-recorded information 1-3. 1. ADIP address 2. Disk drive device Disc manufacturing method

1. Disc 1-1. First, physical characteristics and wobbling tracks in the disk according to the embodiment will be described.

The optical disk of this example belongs to the category of recently developed disks called, for example, DVR (Data & Video Recording), and particularly has a new wobbling system as the DVR system.
The optical disc of this example is an optical disc that records data by the phase change method, and the disc size is 120 mm in diameter. The disc thickness is 1.2 mm. In other words, these are the same as CD (Compact Disc) type discs and DVD (Digital Versatile Disc) type discs in terms of external appearance.

The laser wavelength for recording / reproducing is 405 nm, and so-called blue laser is used. The NA of the optical system is 0.85.
The track pitch of the track on which the phase change mark (phase change mark) is recorded is 0.32 μm and the linear density is 0.12 μm.
The user data capacity is about 23 GB.

Data recording is a groove recording system. That is, a track by a groove (groove) is formed in advance on the disk, and recording is performed on this groove.
As schematically shown in FIG. 1A, on the disk, a groove GV is formed in a spiral shape from the innermost circumference side to the outermost circumference side. As another example, the grooves GV can be formed concentrically.
The disk is driven to rotate by the CLV (constant linear velocity) method to record and reproduce data, but the groove GV is also set to CLV. Therefore, the wobbling wave number of the groove per track increases as it goes to the outer periphery side of the disk.

Such a groove GV is formed by wobbling (meandering) as shown in FIG. 1B to express a physical address.
That is, the left and right side walls of the groove GV meander corresponding to a signal generated based on an address or the like.
A land L is formed between the groove GV and the adjacent groove GV, and data is recorded in the groove GV as described above. That is, the groove GV becomes a data track. It is also conceivable to record data on the land L using the land L as a data track, or to use both the groove GV and the land L as data tracks.

FIG. 2 shows the layout (area configuration) of the entire disc.
As an area on the disc, a lead-in zone, a data zone, and a lead-out zone are arranged from the inner peripheral side.
If you look at the area structure related to recording and playback. The inner circumference side of the lead-in zone is a PB zone (reproduction-only area), and the outer circumference side of the lead-in zone to the lead-out zone is an RW zone (recording / reproduction area).

The lead-in zone is located inside a radius of 24 mm. A radius of 22.3 to 23.1 mm is set as a prerecorded data zone.
In the pre-recorded data zone, information used for copy protection (pre-recorded information) is recorded in advance by wobbling a groove formed in a spiral shape on the disk. This is reproduction-only information that cannot be rewritten, that is, the prerecorded data zone becomes the PB zone (reproduction-only area).

For example, copy protection information is recorded as pre-recorded information in the pre-recorded data zone. For example, the following is performed using this copy protection information.
In the optical disc system according to this example, registered drive device manufacturers and disc manufacturers can conduct business, and have a media key or a drive key indicating that the registration has been performed.
When hacked, the drive key or media key is recorded as copy protection information. With this information, the medium or drive having the media key and the drive key can be made unrecordable.

In the lead-in zone, a test write area and a defect management area are provided at a radius of 23.1 to 24 mm.
The test write area is used for test writing when setting recording / playback conditions for phase change marks such as laser power during recording / playback.
The defect management area records and reproduces information for managing defect information on the disc.

A radius of 24.0 to 58.0 mm is a data zone. The data zone is an area where user data is actually recorded and reproduced by phase change marks.
A radius of 58.0 to 58.5 mm is a lead-out zone. The lead-out zone is provided with a defect management area similar to the lead-in zone, and is used as a buffer area so that overrun may occur during seek.
A radius of 23.1 mm, that is, from the test write area to the lead-out zone is an RW zone (recording / reproducing area) where the phase change mark is recorded / reproduced.

  FIG. 3 shows the tracks in the RW zone and the PB zone. 3A shows groove wobbling in the RW zone, and FIG. 3B shows groove wobbling in the PB zone.

In the RW zone, address information (ADIP) is previously formed by wobbling a groove formed in a spiral shape on the disk in order to perform tracking.
Information is recorded / reproduced by a phase change mark in the groove in which the address information is formed.
As shown in FIG. 3A, a groove in the RW zone, that is, a groove track on which ADIP address information is formed has a track pitch TP = 0.32 μm.
A recording mark by a phase change mark is recorded on this track. The phase change mark is an RLL (1, 7) PP modulation method (RLL: Run Length Limited, PP: Parity preserve / Prohibit rmtr (repeated minimum transition runlength)). ) Etc., the linear density is 0.12 μm / bit and 0.08 μm / ch bit.
If the 1ch bit is 1T, the mark length is 2T to 8T, and the shortest mark length is 2T.
The address information has a wobbling period of 69T and a wobbling amplitude WA of about 20 nm (pp).

The address information and the phase change mark are configured so that their frequency bands do not overlap with each other, thereby preventing each detection from being affected.
The CNR (carrier noise ratio) of wobbling of address information is 30 dB after recording when the bandwidth is 30 KHz, and the address error rate is 1 × 10 ⁻ including the effect of movement (disk skew, defocus, disturbance, etc.). ³ or less.

On the other hand, the track by the groove in the PB zone in FIG. 3B has a wider track pitch and a larger wobbling amplitude than the track by the groove in the RW zone in FIG.
That is, the track pitch TP = 0.35 μm, the wobbling period is 36 T, and the wobbling amplitude WA is approximately 40 nm (pp). A wobbling period of 36T means that the recording linear density of pre-recorded information is higher than the recording linear density of ADIP information. Further, since the phase change mark is 2T at the shortest, the recording linear density of the prerecorded information is lower than the recording linear density of the phase change mark.
No phase change mark is recorded on this PB zone track.

  The wobbling waveform is formed in a sine wave shape in the RW zone, but can be recorded in a sine wave shape or a rectangular wave shape in the PB zone.

If the signal quality is about CNR 50 dB when the bandwidth is 30 KHz, the phase change mark can be recorded / reproduced with ECC (error correction code) added to the data so that the symbol error rate after error correction is 1 × 10 ⁻¹⁶ or less It is known that it can be used for data recording and reproduction.
The wobble CNR for the ADIP address information is 35 dB when the phase change mark is not recorded when the bandwidth is 30 KHz.
As address information, this level of signal quality is sufficient by performing interpolation protection based on so-called continuity discrimination, etc., but for pre-recorded information recorded in the PB zone, CNR 50 dB or more equivalent to the phase change mark I want to ensure the signal quality. Therefore, as shown in FIG. 3B, in the PB zone, a groove physically different from the groove in the RW zone is formed.

First, by widening the track pitch, crosstalk from the adjacent track can be suppressed, and CNR can be improved by +6 dB by doubling the wobble amplitude.
Furthermore, CNR can be improved by +2 dB by using a rectangular wave as a wobble waveform.
In addition, the CNR is 43 dB.
The difference between the wobble recording bands of the phase change mark and the prerecorded data zone is wobble 18T (18T is half of 36T); phase change mark 2T, and 9.5 dB is obtained in this respect.
Therefore, the CNR as prerecorded information is equivalent to 52.5 dB, and even if -2 dB is estimated as crosstalk from the adjacent track, it is equivalent to CNR 50.5 dB. That is, the signal quality is substantially the same as that of the phase change mark, and it is sufficiently appropriate to use the wobbling signal for recording / reproducing prerecorded information.

1-2. Pre-Recorded Information FIG. 4 shows a pre-recorded information modulation method for forming a wobbling groove in the pre-recorded data zone.
The modulation uses FM codes.
FIG. 4A shows the data bits, FIG. 4B shows the channel clock, FIG. 4C shows the FM code, and FIG. 4D shows the wobble waveform vertically.
1 bit of data is 2ch (2 channel clock), and when the bit information is “1”, the FM code has a frequency of 1.2 of the channel clock.
When the bit information is “0”, the FM code is represented by a frequency that is ½ of the bit information “1”.
As the wobble waveform, the FM code may be directly recorded as a rectangular wave, but may be recorded as a sinusoidal waveform as shown in FIG.

  Note that the FM code and the wobble waveform may be patterns opposite in polarity to those shown in FIGS. 4C and 4D, and the patterns shown in FIGS. 4E and 4F.

In the FM code modulation rule as described above, the FM code waveform and wobble waveform (sinusoidal waveform) when the data bit stream is “10110010” as shown in FIG. 4G are shown in FIG. As shown in (i).
In addition, when it corresponds to the pattern shown to FIG.4 (e) (f), it comes to show to FIG.4 (j) (k).

The ECC format for the phase change mark and the pre-recorded information will be described with reference to FIGS.
First, FIG. 5 shows an ECC format for main data (user data) to be recorded / reproduced with a phase change mark.

  There are two types of ECC (Error Correction Code): LDC (long distance code) for main data 64 KB (= 2048 bytes × 32 sectors of 1 sector) and BIS (Burst indicator subcode).

  The main data 64 KB shown in FIG. 5A is ECC encoded as shown in FIG. That is, the main data adds 4B EDC (error detection code) for one sector 2048B, and encodes LDC for 32 sectors. LDC is an RS (reed solomon) code of RS (248, 216, 33), code length 248, data 216, and distance 33. There are 304 code words.

  On the other hand, BIS is ECC-encoded as shown in FIG. 5D with respect to 720B data shown in FIG. That is, the RS (62, 30, 33), code length 62, data 30, and distance 33 RS (reed solomon) code. There are 24 codewords.

FIG. 7A shows a frame structure for main data in the RW zone.
The LDC data and the BIS constitute the frame structure shown in the figure. That is, for each frame, data (38B), BIS (1B), data (38B), BIS (1B), and data (38B) are arranged to form a 155B structure. That is, one frame is configured by inserting 38B × 4 152B data and 1B of BIS for each 38B.
A frame sync FS (frame synchronization signal) is arranged at the head of one frame 155B. There are 496 frames in one block.
In the LDC data, even-numbered codewords 0, 2,... Are located in even-numbered frames 0, 2,. Located in odd-numbered frames 1, 3,.

The BIS uses a code having a much better correction capability than the LDC code, and almost all are corrected. That is, a code having a distance of 33 with respect to the code length 62 is used.
Therefore, the BIS symbol in which an error is detected can be used as follows.
When decoding ECC, BIS is decoded first. In the frame structure of FIG. 7A, when two adjacent BISs or frame sync FSs are in error, the data 38B sandwiched between them is regarded as a burst error. An error pointer is added to each data 38B. The LDC uses this error pointer to correct the pointer erasure.
As a result, the correction capability can be improved as compared with correction using only LDC.
The BIS includes address information and the like. This address is used when there is no address information by a wobbling groove on a ROM type disk or the like.

Next, FIG. 6 shows an ECC format for pre-recorded information.
In this case, there are two ECCs, LDC (long distance code) and BIS (Burst indicator subcode) for main data 4 KB (1 sector 2048 B × 2 sectors).

  The data 4KB as the prerecorded information shown in FIG. 6A is ECC encoded as shown in FIG. 6B. That is, the main data adds 4B EDC (error detection code) for one sector 2048B, and encodes LDC for two sectors. LDC is an RS (reed solomon) code of RS (248, 216, 33), code length 248, data 216, and distance 33. There are 19 code words.

  On the other hand, BIS is ECC-encoded as shown in FIG. 6D with respect to the 120B data shown in FIG. That is, the RS (62, 30, 33), code length 62, data 30, and distance 33 RS (reed solomon) code. There are four code words.

FIG. 7B shows a frame structure for prerecorded information in the PB zone.
The LDC data and the BIS constitute the frame structure shown in the figure. That is, for each frame, the frame sync FS (1B), data (10B), BIS (1B), and data (9B) are arranged to form a 21B structure. That is, one frame is configured by inserting 19B data and 1B BIS.
A frame sync FS (frame synchronization signal) is arranged at the head of one frame. There are 248 frames in one block.

Also in this case, the BIS uses a code having a much better correction capability than the LDC code, and almost all are corrected. Therefore, the BIS symbol in which an error is detected can be used as follows.
When decoding ECC, BIS is decoded first. When two adjacent BISs or frame sync FSs are in error, the data 10B or 9B sandwiched between them is regarded as a burst error. An error pointer is added to each of the data 10B or 9B. The LDC uses this error pointer to correct the pointer erasure.
As a result, the correction capability can be improved rather than the correction only by the LDC.

  The BIS includes address information and the like. In the prerecorded data zone, prerecorded information is recorded by the wobbling groove, and therefore there is no address information by the wobbling groove, so the address in this BIS is used for access.

As can be seen from FIGS. 5 and 6, the same code and structure are adopted as the ECC format for the data by the phase change mark and the pre-recorded information.
This means that ECC decoding processing of pre-recorded information can be executed by a circuit system that performs ECC decoding processing at the time of data reproduction by phase change marks, and the disk drive device can improve the efficiency of the hardware configuration. To do.

FIG. 8 shows the frame sync of the prerecorded data zone.
As the frame sync FS, there are seven types of frame syncs FS0 to FS6. Each of the frame syncs FS0 to FS6 uses a pattern as an out-of-rule of FM code modulation, 8 channel bits of the sync body “11001001”, and 8 channel bits of a sync ID for each of the seven types of frame syncs FS0 to FS6 The total of 16 channel bits.

When the sync ID is represented by a data bit, for example, the frame sync FS0 is represented by 3 bits of “000” and 1 bit of parity (0 in this case), which is FM code modulated to “10101010”.
Similarly, other sync IDs are represented by 3 bits of data bits and 1 bit of parity, and are FM code modulated.
The frame sync FS is recorded after NRZI conversion at the time of recording.

FIG. 9 shows the frame sync mapping.
The 248 frames of one ECC block of the pre-recorded information shown in FIG. 7B is divided into eight 31-frame address frames.
Each address frame has a frame number from 0 to 30. For the frame number “0”, FS0 is used as a special frame sync that is not used for other frame syncs. With this frame sync FS0, the head of the address frame can be found and address synchronization can be performed.
In frame numbers “1” to “30”, frame syncs (FS1 to FS6) are arranged in the order shown in FIG. Depending on the order in which the frame syncs are arranged, the head of the address frame can be specified even if the head frame sync FS0 cannot be specified.

By the way, it has been stated that in the prerecorded data zone, the address included in the BIS is used for access.
FIG. 10 shows information put in the BIS in the ECC block of the prerecorded data zone.
The BIS information is composed of an address and user control data.

The address field in BIS is shown in FIG. As addresses, there are 8 address fields (# 0 to # 7) in one ECC block.
One address field is composed of 9 bytes. For example, the address field # 0 is composed of 9 bytes A0-0 to A0-8.
An address value indicating an ECC block address called AUN (address unit number) is arranged in MSB 4 Byte of each address field.
In the fifth byte of each address field, an address field number is arranged in the lower 3 bits (3 Lsbit).
Further, the parity for each address field is arranged in the lower 4 bytes of each address field.

On the other hand, user control data in BIS is 2 units (# 0, # 1) in one ECC block as shown in FIG.
One unit of user control data is composed of 24 bytes. For example, unit # 0 is composed of 24 bytes UC0-0 to UC0-23.
This user control data is reserved for use in future systems.

FIG. 11 shows the configuration of the BIS of the ECC block in the prerecorded data zone, that is, the BIS information of the BIS cluster.
The BIS cluster is composed of 4 correction codes. Here, only the information excluding the parity is shown. The code is configured in the column direction of the figure. A BIS cluster consists of four columns.
One column of information is composed of a total of 30 rows of 18 rows of addresses and 12 rows of user control data.

The addresses of the address fields # 0 to # 7 are arranged to be interleaved into 4 columns as shown in the figure. Here, only the address fields # 0, # 1, and # 2 are shown. For example, the 9 bytes of A0-0 to A0-8 constituting the address field # 0 are located at the positions indicated by hatching in the figure. Will be placed.
In the user control data, units # 0 and # 1 are arranged in the range of 12 rows as shown in the figure.
When recording, for example, recording is performed in the tan direction of the BIS cluster so that the address field # 0 shown in the figure is sequentially arranged.

FIG. 12 shows the entire BIS cluster including parity.
The error correction code of BIS is RS (62, 30, 33) as described above. The BIS cluster has four codes with a code length of 62 symbols, and one code is encoded in the vertical direction as indicated by an arrow in the figure.

FIG. 13 shows the order of recording 248 symbols of the BIS cluster including parity.
A BIS cluster is recorded as an 8-address unit during recording.
One address unit is composed of 31 symbols as shown in FIG.
In the first 9 bytes of each address unit, 9 bytes (An-0 to An-8) as an address field #n of a number corresponding to each address unit number are arranged. For example, address field # 0 (A0-0 to A0-8) is arranged in address unit 0.
For example, 31 symbols as such an address unit 0 are arranged as shown by hatched portions in FIG.

  31 symbols of one address unit correspond to the 31 address frame described above, and the timing of one address unit can be detected from the timing of frame sync FS0 by the frame number and frame sync pattern (FS0 to FS6) of FIG. Thus, the addresses in the address fields (# 0 to # 7) can be reproduced.

1-3. ADIP Address Next, an ADIP address recorded as a wobbling groove in the RW zone will be described.
FIG. 15 shows a method using MSK (minimum shift keying) modulation, which is one of FSK modulation, as a method of modulating an ADIP address with wobbling a groove.

The detection length of data is in units of 2 wobble sections. Note that one wobble section is one period section of wobble with a carrier frequency.
As shown in FIGS. 15A and 15B, data such as addresses is differentially encoded in units of one wobble before recording.
In other words, in the pre-coded data after differential encoding before recording, one wobble period of rising and falling edges of data “1” is “1”.
In an MSK stream obtained by MSK modulating such precode data, as shown in FIG. 15C, when the precode data is “0”, the carrier is cosωt or −cosωt, and the precode data is “1”. Then, it becomes cos1.5ωt or −cos1.5ωt which is 1.5 times the frequency of the carrier.
As shown in the figure, the carrier period is 69 ch if the 1 channel bit length of phase change data to be recorded / reproduced is 1 ch.

In the case of this example, one RUB (recording unit block: recording / reproducing cluster) which is a data recording unit is assumed to have three addresses as ADIP addresses.
This is shown in FIG. The RUB (recording / reproducing cluster) is a unit of recording / reproducing as 498 frames obtained by adding a link area for two frames of PLL or the like to the 496 frames of the ECC block of the data shown in FIG. .
Then, in the section corresponding to one RUB as shown in FIG. 16A, three address blocks are included as ADIP.
One address block is formed from 83 bits.

FIG. 16B shows the configuration of one address block. The 83-bit address block is composed of an 8-bit sync part (synchronization signal part) and a 75-bit data part.
In the 8 bits of the sync part, 4 units of sync blocks are formed by monotone bits (1 bit) and sync bits (1 bit).
In the 75 bits of the data part, 15 units of ADIP blocks are formed by monotone bits (1 bit) and ADIP bits (4 bits).
The monotone bit, the sync bit, and the ADIP bit are each formed by 56 wobble periods. An MSK mark for bit sync is arranged at the head of these bits.
In the monotone bit, a wobble with a carrier frequency is continuously formed following the MSK mark. Although the sync bit and the ADIP bit will be described later, the sync bit and the ADIP bit are formed with a wobble by an MSK modulation waveform following the MSK mark.

First, the configuration of the sync part will be described with reference to FIG.
As can be seen from FIGS. 17A and 17B, the 8-bit sync part is formed of four sync blocks (sync block “0” “1” “2” “3”). Each sync block is 2 bits.

The sync block “0” is formed by a monotone bit and a sync “0” bit.
The sync block “1” is formed by a monotone bit and a sync “1” bit.
The sync block “2” is formed of a monotone bit and a sync “2” bit.
The sync block “3” is formed by a monotone bit and a sync “3” bit.

In each sync block, the monotone bit is a waveform in which a single frequency wobble representing a carrier continues as described above, and this is shown in FIG. In other words, during the 56 wobble period, an MSK mark as a bit sync bs is added to the head, followed by a single frequency wobble.
In FIGS. 18A to 18E, the MSK mark pattern is shown in the lower part of the wobble amplitude.

As described above, there are four types of sync bits from sync “0” bit to sync “3” bit.
Each of these four types of sync bits has a wobble pattern as shown in FIGS. 18B, 18C, 18D, and 18E.

The sync “0” bit in FIG. 18B has a pattern in which there is an MSK mark after 16 wobble sections and an MSK mark after 10 wobble sections following the MSK mark as the bit sync bs.
The sync “1” bit to sync “3” bit are patterns in which the position of the MSK mark is shifted backward by 2 wobble sections.
That is, the sync “1” bit in FIG. 18C has a pattern in which there is an MSK mark after 18 wobble sections and an MSK mark after 10 wobble sections following the MSK mark as the bit sync bs.
The sync “2” bit in FIG. 18D has a pattern in which there is an MSK mark after 20 wobble sections, followed by an MSK mark after 10 wobble sections, following the MSK mark as the bit sync bs.
The sync “3” bit in FIG. 18E has a pattern in which there is an MSK mark after 22 wobble sections, and an MSK mark after 10 wobble sections following the MSK mark as the bit sync bs.

  Each sync pattern is a unique pattern for a monotone bit and an ADIP bit described below. In this way, four patterns of sync bits are arranged in each sync block, and if the disk drive device can detect any one of the four patterns of sync units from the sync part section, synchronization is achieved. Have been able to.

Next, the structure of the data part in the address block will be described with reference to FIG.
As can be seen from FIGS. 19A and 19B, the data part is formed of 15 ADIP blocks (ADIP blocks “0” to “14”). Each ADIP block is 5 bits.

Each 5-bit ADIP block is composed of 1 monotone bit and 4 ADIP bits.
In each ADIP block, as in the case of the sync block, the monotone bit has a waveform in which the MSK mark as the bit sync bs is arranged at the head in the 56 wobble period, and the wobble of the carrier frequency continues, and this is shown in FIG. This is shown in (a).

Since 4 ADIP bits are included in one ADIP block, address information is formed with 15 ADIP blocks with 60 ADIP bits.
FIGS. 20B and 20C show patterns of “1” and “0” as ADIP bits.
As shown in FIG. 20B, the wobble waveform pattern when the value as the ADIP bit is “1” is the MSK mark behind the 12 wobble section following the MSK mark as the bit sync bs arranged at the head. Is arranged.
As shown in FIG. 20C, the wobble waveform pattern when the value as the ADIP bit is “0” is the MSK mark behind the 14 wobble section following the MSK mark as the bit sync bs arranged at the head. Is arranged.

  As described above, MSK modulation data is recorded in the wobbling groove, and the address format as ADIP information recorded in this way is as shown in FIG.

FIG. 21 shows an error correction method for ADIP address information.
ADIP address information has 36 bits, and a parity of 24 bits is added thereto.
36-bit ADIP address information consists of 3 bits for layer recording (layer no.bit 0 to layer no.bit2) and 19 bits for RUB (recording unit block) (RUB no.bit 0 to layer no.bit 18). 2 bits (address no.bit 0, address no.bit1) are used for three address blocks for one RUB.
In addition, 12 bits are prepared as AUX data such as disc ID in which recording conditions such as recording / reproducing laser power are recorded.

The ECC unit as address data is thus a unit of 60 bits in total, and is composed of 15 nibbles (1 nibble = 4 bits) of Nibble0 to Nibble14 as shown.
The error correction method is a nibble-based Reed-Solomon code RS (15, 9, 7) with 4 bits as one symbol. That is, the code length is 15 nibbles, the data is 9 nibbles, and the parity is 6 nibbles.

2. Disc Drive Device Next, a disc drive device capable of recording / reproducing corresponding to the above disc will be described.
FIG. 22 shows the configuration of the disk drive device.
In FIG. 22, a disk 100 is the disk of this example described above.

The disk 100 is loaded on a turntable (not shown) and is driven to rotate at a constant linear velocity (CLV) by the spindle motor 2 during a recording / reproducing operation.
The ADIP information embedded as wobbling of the groove track in the RW zone on the disc 100 is read by the optical pickup 1. Further, pre-recorded information embedded as wobbling of the groove track in the PB zone is read out.
At the time of recording, user data is recorded as a phase change mark on the track in the RW zone by the optical pickup, and at the time of reproduction, the phase change mark recorded by the optical pickup is read out.

In the pickup 1, a laser diode serving as a laser light source, a photodetector for detecting reflected light, an objective lens serving as an output end of the laser light, and a laser recording light are irradiated onto the disk recording surface via the objective lens. An optical system (not shown) for guiding the reflected light to the photodetector is formed.
The laser diode outputs a so-called blue laser having a wavelength of 405 nm. The NA by the optical system is 0.85.

In the pickup 1, the objective lens is held so as to be movable in the tracking direction and the focus direction by a biaxial mechanism.
The entire pickup 1 can be moved in the disk radial direction by the thread mechanism 3.
The laser diode in the pickup 1 is driven to emit laser light by a drive signal (drive current) from the laser driver 13.

Reflected light information from the disk 100 is detected by a photo detector, converted into an electric signal corresponding to the amount of received light, and supplied to the matrix circuit 4.
The matrix circuit 4 includes a current-voltage conversion circuit, a matrix calculation / amplification circuit, and the like corresponding to output currents from a plurality of light receiving elements as photodetectors, and generates necessary signals by matrix calculation processing.
For example, a high frequency signal (reproduction data signal) corresponding to reproduction data, a focus error signal for servo control, a tracking error signal, and the like are generated.
Further, a push-pull signal is generated as a signal related to groove wobbling, that is, a signal for detecting wobbling.

  The reproduction data signal output from the matrix circuit 4 is supplied to the reader / writer circuit 5, the focus error signal and tracking error signal are supplied to the servo circuit 11, and the push-pull signal is supplied to the wobble circuit 8.

The reader / writer circuit 5 performs binarization processing on the reproduction data signal, reproduction clock generation processing by PLL, etc., reproduces the data read as the phase change mark, and supplies it to the modulation / demodulation circuit 6.
The modem circuit 6 includes a functional part as a decoder during reproduction and a functional part as an encoder during recording.
At the time of reproduction, as a decoding process, a run-length limited code is demodulated based on the reproduction clock.
The ECC encoder / decoder 7 performs ECC encoding processing for adding an error correction code at the time of recording and ECC decoding processing for error correction at the time of reproduction.
At the time of reproduction, the data demodulated by the modulation / demodulation circuit 6 is taken into an internal memory, and error detection / correction processing and deinterleaving processing are performed to obtain reproduction data.
The data decoded up to the reproduction data by the ECC encoder / decoder 7 is read based on an instruction from the system controller 10 and transferred to an AV (Audio-Visual) system 20.

The push-pull signal output from the matrix circuit 4 as a signal related to groove wobbling is processed in the wobble circuit 8. The push-pull signal as ADIP information is MSK demodulated in the wobble circuit 8, demodulated into a data stream constituting an ADIP address, and supplied to the address decoder 9.
The address decoder 9 decodes the supplied data, obtains an address value, and supplies it to the system controller 10.
The address decoder 9 generates a clock by PLL processing using the wobble signal supplied from the wobble circuit 8, and supplies it to each unit as an encode clock at the time of recording, for example.

Further, as a push-pull signal output from the matrix circuit 4 as a signal related to the wobbling of the groove, a push-pull signal as pre-recorded information from the PB zone is subjected to band-pass filter processing in the wobble circuit 8 to be read / read It is supplied to the writer circuit 5. Then, as in the case of the phase change mark, it is binarized and made into a data bit stream, and then ECC decoded and deinterleaved by the ECC encoder / decoder 7 to extract data as prerecorded information. The extracted prerecorded information is supplied to the system controller 10.
The system controller 10 can perform various setting processes and copy protection processes based on the read prerecorded information.

At the time of recording, recording data is transferred from the AV system 20, and the recording data is sent to a memory in the ECC encoder / decoder 7 and buffered.
In this case, the ECC encoder / decoder 7 performs error correction code addition, interleaving, subcode addition, and the like as an encoding process of the buffered recording data.
The ECC-encoded data is subjected to RLL (1-7) PP modulation in the modulation / demodulation circuit 6 and supplied to the reader / writer circuit 5.
As described above, the clock generated from the wobble signal is used as the reference clock for the encoding process during recording.

The recording data generated by the encoding process is subjected to a recording compensation process by the reader / writer circuit 5 and fine adjustment of the optimum recording power and adjustment of the laser drive pulse waveform with respect to the recording layer characteristics, laser beam spot shape, recording linear velocity, etc. Etc. are sent to the laser driver 13 as a laser drive pulse.
The laser driver 13 applies the supplied laser drive pulse to the laser diode in the pickup 1 to perform laser emission driving. As a result, pits (phase change marks) corresponding to the recording data are formed on the disc 100.

  The laser driver 13 includes a so-called APC circuit (Auto Power Control), and the laser output is not dependent on temperature or the like while monitoring the laser output power by the output of the laser power monitoring detector provided in the pickup 1. Control to be constant. The target value of the laser output at the time of recording and reproduction is given from the system controller 10, and the laser output level is controlled to be the target value at the time of recording and reproduction.

The servo circuit 11 generates various servo drive signals for focus, tracking, and sled from the focus error signal and tracking error signal from the matrix circuit 4 and executes the servo operation.
That is, the focus drive signal and the tracking drive signal are generated according to the focus error signal and the tracking error signal, and the focus coil and tracking coil of the biaxial mechanism in the pickup 1 are driven. As a result, the pickup 1, the matrix circuit 4, the servo circuit 11, the tracking servo loop and the focus servo loop by the biaxial mechanism are formed.

  The servo circuit 11 executes a track jump operation by turning off the tracking servo loop and outputting a jump drive signal in response to a track jump command from the system controller 10.

  The servo circuit 11 generates a thread drive signal based on a thread error signal obtained as a low frequency component of the tracking error signal, access execution control from the system controller 10, and the like, and drives the thread mechanism 3. Although not shown, the thread mechanism 3 includes a mechanism including a main shaft that holds the pickup 1, a thread motor, a transmission gear, and the like, and a required slide of the pickup 1 by driving the thread motor in accordance with a thread drive signal. Movement is performed.

The spindle servo circuit 12 performs control to rotate the spindle motor 2 at CLV.
The spindle servo circuit 12 obtains the clock generated by the PLL processing for the wobble signal as the current rotational speed information of the spindle motor 2, and compares it with predetermined CLV reference speed information to generate a spindle error signal. .
At the time of data reproduction, the reproduction clock (clock serving as a reference for decoding processing) generated by the PLL in the reader / writer circuit 5 becomes the current rotational speed information of the spindle motor 2 and is used as a predetermined CLV. A spindle error signal can also be generated by comparing with the reference speed information.
The spindle servo circuit 12 outputs a spindle drive signal generated according to the spindle error signal, and causes the spindle motor 2 to perform CLV rotation.
Further, the spindle servo circuit 12 generates a spindle drive signal in response to a spindle kick / brake control signal from the system controller 10, and also executes operations such as starting, stopping, acceleration, and deceleration of the spindle motor 2.

Various operations of the servo system and the recording / reproducing system as described above are controlled by a system controller 10 formed by a microcomputer.
The system controller 10 executes various processes according to commands from the AV system 20.

  For example, when a write command (write command) is issued from the AV system 20, the system controller 10 first moves the pickup 1 to an address to be written. Then, the ECC encoder / decoder 7 and the modulation / demodulation circuit 6 perform the encoding process as described above on the data transferred from the AV system 20 (for example, video data of various systems such as MPEG2 or audio data). Then, recording is executed by supplying the laser drive pulse from the reader / writer circuit 5 to the laser driver 13 as described above.

For example, when a read command for transferring certain data (MPEG2 video data or the like) recorded on the disc 100 is supplied from the AV system 20, seek operation control is first performed for the instructed address. That is, a command is issued to the servo circuit 11 to cause the pickup 1 to access the address specified by the seek command.
Thereafter, operation control necessary for transferring the data in the designated data section to the AV system 20 is performed. That is, data reading from the disk 100 is performed, decoding / buffering and the like in the reader / writer circuit 5, the modulation / demodulation circuit 6, and the ECC encoder / decoder 7 are executed, and the requested data is transferred.

  When recording / reproducing data using these phase change marks, the system controller 10 controls access and recording / reproducing operations using the ADIP address detected by the wobble circuit 8 and the address decoder 9.

Further, at a predetermined time such as when the disc 100 is loaded, the system controller 10 causes the prerecorded information recorded in the PB zone of the disc 100 to be read as a wobbling groove.
In that case, seek operation control is first performed for the purpose of the PB zone. That is, a command is issued to the servo circuit 11 to cause the pickup 1 to access the innermost circumference of the disk.
Thereafter, a reproduction trace by the pickup 1 is executed to obtain a push-pull signal as reflected light information, and a decoding process by the wobble circuit 8, the reader / writer circuit 5 and the ECC encoder / decoder 7 is executed to obtain prerecorded information. Get playback data.
The system controller 10 performs laser power setting, copy protection processing, and the like based on the prerecorded information read out in this way.

  At the time of reproducing the pre-recorded information in the PB zone, the system controller 10 controls access and reproduction operations using the address information included in the BIS cluster as the read pre-recorded information.

Incidentally, although the example of FIG. 22 is the disk drive device 30 connected to the AV system 20, the disk drive device of the present invention may be connected to, for example, a personal computer.
Furthermore, there may be a form that is not connected to other devices. In that case, an operation unit and a display unit are provided, and the configuration of the interface portion for data input / output is different from that in FIG. That is, it is only necessary that recording and reproduction are performed in accordance with a user operation and a terminal unit for inputting / outputting various data is formed.
Of course, there are various other configuration examples. For example, examples of a recording-only device and a reproduction-only device are also possible.

The MSK demodulation system concerning the push-pull signal as ADIP information in the wobble circuit 8 will be described with reference to FIGS.
As a configuration for MSK demodulation, the wobble circuit 8 is provided with bandpass filters 51 and 52, a multiplier 53, a lowpass filter 54, and a slicer 55 as shown in FIG.

As described above, for example, address data as ADIP information as shown in FIG. 24A is pre-coded data differentially encoded as shown in FIG. 24B, and as shown in FIG. 24C. MSK modulated. The groove is wobbled on the disk based on the MSK modulation signal.
Therefore, at the time of recording / reproducing in the RW zone of the disc 100, information obtained as a push-pull signal is a signal corresponding to the MSK modulation waveform in FIG.

The push-pull signal P / P supplied from the matrix circuit 9 in FIG. 22 as a signal related to wobbling is supplied to each of the bandpass filters 51 and 52 in FIG.
The band-pass filter 51 has a characteristic of passing a carrier frequency and a band corresponding to 1.5 times the carrier frequency, and the band-pass filter 51 extracts a wobble component, that is, the MSK modulated wave of FIG. Is done.
The bandpass filter 52 has narrower band characteristics that allow only the carrier frequency component to pass through, and the carrier component shown in FIG. 24D is extracted.

Multiplier 53 multiplies the outputs of bandpass filters 51 and 52. That is, synchronous detection can be performed by multiplying the MSK modulated wobble signal by the carrier, and the demodulated signal demod out of FIG. 24 (e) is obtained.
By passing the demodulated signal demod out through the next LPF 54, the LPF out signal of FIG. 24 (f) is obtained.
The LPF 54 is, for example, a 27-tap FIR filter, and the coefficients are as follows.

-0.000640711
-0.000865006
0.001989255
0.009348803
0.020221675
0.03125
0.040826474
0.050034929
0.05852149
0.065960023
0.072064669
0.076600831
0.079394185
0.080337385; Center
0.079394185
0.076600831
0.072064669
0.065960023
0.05852149
0.050034929
0.040826474
0.03125
0.020221675
0.009348803
0.001989255
-0.000865006
-0.000640711

The LPF out signal obtained from such an LPF 54 is binarized by a slicer 55 formed as a comparator, thereby obtaining demodulated data (demod data) shown in FIG.
The demodulated data (demod data) which is the binarized output becomes channel bit data forming address information, and is supplied to the address decoder 9 shown in FIG. 22 to decode the ADIP address.

3. Disc Manufacturing Method Subsequently, the manufacturing method of the above-described disc of this example will be described.
The disc manufacturing process is roughly divided into a so-called master process (mastering process) and a disc forming process (replication process). The master process is a process until the completion of a metal master (stamper) used in the disc making process, and the disc making process is a process for mass-producing an optical disc as a duplicate using the stamper.

Specifically, in the master process, so-called cutting is performed in which a photoresist is applied to a polished glass substrate, and pits and grooves are formed on the photosensitive film by exposure with a laser beam.
In the case of this example, groove cutting is performed by wobbling based on pre-recorded information in the portion corresponding to the PB zone on the innermost circumference side of the disk, and wobbling based on the ADIP address in the portion corresponding to the RW zone. Groove cutting is performed.

The prerecorded information to be recorded is prepared in a preparation process called premastering.
When the cutting is completed, after performing a predetermined process such as development, information is transferred onto the metal surface by, for example, electroforming, and a stamper necessary for copying the disk is created.
Next, using this stamper, the information is transferred onto a resin substrate by, for example, an injection method, and after a reflective film is formed thereon, processing such as processing into a required disk form is performed to obtain a final product. Complete.

For example, as shown in FIG. 25, the cutting apparatus includes a prerecorded information generation unit 71, an address generation unit 72, a switching unit 73, a cutting unit 74, and a controller 70.
The prerecorded information generating unit 71 outputs prerecorded information prepared in the premastering process.
The address generator 72 sequentially outputs values as absolute addresses.

  The cutting unit 74 includes an optical unit (82, 83, 84) that performs cutting by irradiating a laser beam onto the photoresist glass substrate 101, and a substrate rotation / transfer unit 85 that rotationally drives and slides the glass substrate 101. The cutting position can be discriminated from the PB zone or the RW zone from the position of the signal processing unit 81 that converts the input data into recording data and supplies it to the optical unit and the position of the substrate rotation / transfer unit 85. It has a sensor 86.

As the optical unit, for example, a laser light source 82 composed of a He—Cd laser, a modulation unit 83 that modulates light emitted from the laser light source 82 based on recording data, and a modulated beam from the modulation unit 83 is condensed. A cutting head portion 84 for irradiating the photoresist surface of the glass substrate 101 is provided.
The modulation unit 83 includes an acousto-optic type optical modulator (AOM) that turns on and off the light emitted from the laser light source 82, and an acousto-optic type that deflects the light emitted from the laser light source 82 based on the wobble generation signal. An optical deflector (AOD) is provided.

  The substrate rotation / transfer unit 85 includes a rotation motor that rotates the glass substrate 101, a detection unit (FG) that detects the rotation speed of the rotation motor, and a slide motor that slides the glass substrate 101 in the radial direction. And a servo controller for controlling the rotation speed of the rotary motor and slide motor, the tracking of the cutting head portion 84, and the like.

For example, the signal processing unit 81 adds, for example, an error correction code or the like to prerecorded information or address information supplied via the switching unit 73 to form input data, or formatting processing data. A modulation signal generation process is performed in which a predetermined arithmetic process is performed to form a modulation signal.
Based on the modulation signal, drive processing for driving the optical modulator and the optical deflector of the modulator 83 is also performed.

In the cutting unit 74, when cutting, the substrate rotation / transfer unit 85 drives the glass substrate 101 to rotate at a constant linear velocity, and a spiral track is formed at a predetermined track pitch while rotating the glass substrate 71. Slide as you go.
At the same time, the light emitted from the laser light source 82 is converted into a modulated beam based on the modulation signal from the signal processing unit 81 via the modulation unit 83 and is irradiated onto the photoresist surface of the glass substrate 71 from the cutting head unit 84. As a result, the photoresist is exposed based on data and grooves.

The controller 70 controls execution of the cutting operation of the cutting unit 74 and controls the prerecorded information generation unit 71, the address generation unit 72, and the switching unit 73 while monitoring the signal from the sensor 86.
At the start of cutting, the controller 70 sets the slide position of the substrate rotation / transfer unit 85 as the initial position so that the cutting head 84 starts laser irradiation from the innermost side with respect to the cutting unit 74. Then, CLV rotation driving of the glass substrate 101 and slide transfer for forming a groove with a track pitch of 0.35 μm are started.
In this state, pre-recorded information is output from the pre-recorded information generating unit 71 and supplied to the signal processing unit 81 via the switching unit 73. Further, the laser output from the laser light source 82 is started, and the modulation unit 83 modulates the laser beam based on the modulation signal from the signal processing unit 81, that is, the FM code modulation signal of the pre-recorded information, and outputs the laser beam to the glass substrate 101. Perform groove cutting.
As a result, the groove cutting as shown in FIG. 3B described above is performed in the region corresponding to the PB zone.

After that, when the controller 70 detects from the signal of the sensor 86 that the cutting operation has advanced to a position corresponding to the PB zone, the controller 70 switches the switching unit 73 to the address generating unit 72 side and sequentially converts the address values from the address generating unit 72. Instruct to generate.
In addition, the slide transfer speed is reduced in the substrate rotation / transfer section 85 so as to form grooves with a track pitch of 0.32 μm.

As a result, the address information is supplied from the address generation unit 72 to the signal processing unit 81 via the switching unit 73. The laser light from the laser light source 82 is modulated by the modulation unit 83 based on the modulation signal from the signal processing unit 81, that is, the MSK modulation signal of the address information, and the groove cutting on the glass substrate 101 is executed by the modulation laser light. Is done.
As a result, the groove cutting as shown in FIG. 3A described above is performed in the region corresponding to the RW zone.
When the controller 70 detects from the signal of the sensor 86 that the cutting operation has reached the end of the lead-out zone, the controller 70 ends the cutting operation.

By such an operation, exposure portions corresponding to the wobbling grooves as the PB zone and the RW zone are formed on the glass substrate 101.
Thereafter, development, electroforming, and the like are performed to produce a stamper, and the above-described disk is produced using the stamper.

  The disk of the embodiment, the disk drive device corresponding to the disk, and the disk manufacturing method have been described above, but the present invention is not limited to these examples, and various modifications can be considered within the scope of the gist. It is.

  1 pickup, 2 spindle motor, 3 thread mechanism, 4 matrix circuit, 5 reader / writer circuit, 6 modulation / demodulation circuit, 7 ECC encoder / decoder, 8 wobble circuit, 9 address decoder, 10 system controller, 11 servo circuit, 12 spindle servo Circuit, 13 Laser driver, 20 AV system, 51, 52 Band pass filter, 53 Multiplier, 54 Low pass filter, 55 Slicer, 70 Controller, 71 Pre-recorded information generating unit, 72 Address generating unit, 73 Switching unit, 74 Cutting Part, 100 discs

Claims (3)

Grooves for forming tracks on the disc are formed in a spiral shape,
Address information is recorded by wobbling the groove, and a recording / reproducing area in which a track formed by the groove is used for recording / reproducing a recording mark;
A read-only area where prerecorded information is recorded by wobbling the groove,
Have
The data recorded by the recording mark in the recording / reproducing area includes a frame synchronization signal arranged at the head, user data divided by 38 bytes error-encoded with a long distance code, and each 38 bytes. Is composed of a predetermined number of units consisting of a burst error detection code inserted for each user data divided into
The unit of data recorded with recording marks in the recording / reproducing area is configured by inserting three burst error detection codes between the four user data,
Address information by wobbling of the groove in a section corresponding to the predetermined number of units of data recorded with recording marks in the recording / playback area is composed of a plurality of address blocks each including a sync part and a data part. A first sync block comprising a monotone bit and a first sync bit, a second sync block comprising a monotone bit and a second sync bit, a third sync block comprising a monotone bit and a third sync bit, a monotone A disk recording medium comprising a fourth sync block consisting of a bit and a fourth sync bit . A groove for forming a track on a disk is formed in a spiral shape, and address information is recorded by wobbling the groove, and a track formed by the groove is used for recording / reproduction of a recording mark. A recording-only area in which pre-recorded information is recorded by wobbling of the groove, and data recorded with a recording mark in the recording / reproducing area includes a frame synchronization signal arranged at the head, It is composed of a predetermined number of units consisting of user data delimited every 38 bytes error-corrected and encoded with a distance code, and burst error detection codes inserted for each 38-byte delimited user data. The data recorded with recording marks in the recording / playback area Consists of four are inserted three burst error detection code during said user data, wobbling of the groove in the section corresponding to the predetermined number of units of data recorded by the recording marks on the recording and reproduction area Address information consists of a plurality of address blocks consisting of a sync part and a data part, and the sync part consists of a first sync block consisting of a monotone bit and a first sync bit, a monotone bit and a second sync bit. For a disc recording medium comprising a second sync block, a third sync block consisting of monotone bits and third sync bits, and a fourth sync block consisting of monotone bits and fourth sync bits , A disk drive device for recording or reproducing,
Head means for irradiating the track with laser to obtain a reflected light signal;
Wobbling extraction means for extracting a signal related to wobbling of the track from the reflected light signal;
Recording mark extraction means for extracting a signal related to recording mark information from the reflected light signal;
Address decoding means for performing MSK demodulation on the signal related to the wobbling extracted by the wobbling extraction means and decoding the address information at the time of reproducing the recording / reproducing area;
Phase change mark decoding means for performing decoding processing on the signal related to the recording mark extracted by the recording mark extracting means at the time of reproduction of the recording / reproducing area, and obtaining information recorded as a recording mark;
Pre-recorded information decoding means for decoding the signal related to the wobbling extracted by the wobbling extracting means and obtaining the pre-recorded information at the time of reproduction of the read-only area;
A disk drive device comprising: A groove for forming a track on a disk is formed in a spiral shape, and address information is recorded by wobbling the groove, and a track formed by the groove is used for recording / reproduction of a recording mark. A recording-only area in which pre-recorded information is recorded by wobbling of the groove, and data recorded with a recording mark in the recording / reproducing area includes a frame synchronization signal arranged at the head, It is composed of a predetermined number of units consisting of user data delimited every 38 bytes error-corrected and encoded with a distance code, and burst error detection codes inserted for each 38-byte delimited user data. The data recorded with recording marks in the recording / playback area Consists of four are inserted three burst error detection code during said user data, wobbling of the groove in the section corresponding to the predetermined number of units of data recorded by the recording marks on the recording and reproduction area Address information consists of a plurality of address blocks consisting of a sync part and a data part, and the sync part consists of a first sync block consisting of a monotone bit and a first sync bit, a monotone bit and a second sync bit. As a playback method for a disc recording medium composed of a second sync block, a third sync block consisting of monotone bits and third sync bits, and a fourth sync block consisting of monotone bits and fourth sync bits ,
When playing back the recording / playback area,
A signal related to the wobbling of the track and a signal related to the recording mark are extracted from the reflected light signal when the laser is irradiated to the track, and the address information is obtained by performing MSK demodulation on the extracted signal related to the wobbling. And obtaining the information recorded as the recording mark by performing a decoding process on the signal related to the extracted recording mark,
During playback of the playback-only area,
A reproduction method for extracting pre-recorded information by extracting a signal related to wobbling of a track from a reflected light signal when a track is irradiated with laser, and decoding the extracted signal related to wobbling.

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